The subject of the invention is a method of preparing dihalogen vinylcyclopropanecarboxylic acid esters of the general formula ##STR3## in which R.sup.1 is a straight-chain or branched alkyl moiety and X represents chlorine or bromine.
The moiety R.sup.1 is, for example, an alkyl moiety having 1 to 18, preferably 1 to 8 carbon atoms, especially 1 to 2 carbon atoms.
Known methods of preparing compounds of Formula I are described in German Offenlegungsschrift Nos. 2,606,635 and 2,649,856. Both methods set out from a 3,3-dimethylbutene-1 bifunctionalized in position 4, from which compounds of Formula I are obtained by adding on CCl.sub.4, for example, and then cyclizing with bases. In both methods, staring materials are used which are difficult to obtain, so that the entire process is uneconomical and difficult.